1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) projector, and more particularly to a portable LCD projector including an optical part and a mechanical part both contained in a bag-type housing.
2. Description of the Prior Art
Various types of portable television sets are known such as a cathode-ray tube (CRT) television set having a screen of about five to six inches and, an LCD pocket television set having a screen of about three to four inches and using a back light illuminated at the rear side of a color LCD.
A typical rear projection type LCD projector is illustrated in FIG. 1 which comprises a lighting unit, an image display unit and a projection unit. The lighting unit includes a lamp 1, a reflector 2 and a condensing lens 3. The image display unit is an LCD 5 which is driven by a television circuit 4. And the projection unit includes a projection lens 6 and a rear projection type screen 7 which forms an image projected from the LCD 5 and diffracts an incident light toward a viewer side. The lighting unit is adapted to condense a light emitted from the lamp 1 and illuminate uniformly the LCD 5, and the LCD 5 is adapted to control the transmittance of light depending upon the television image by being driven by the image signals which are input from the television circuit 4.
The projection lens 6 of the projection unit is adapted to form a picture on the rear projection screen 7 by projecting a light from the LCD 5 and the rear projection screen 7 disperses the light at various angles to make the brightness of screen uniform and allows the screen to be watched at various directions.
In accordance with the prior art as discussed above, however, the portable television sets such as the small-sized CRT television and the LCD television, are limited in their screen size to five to six inches or three to four inches, so that it is unsuitable to fully enjoy the picture image; Also, the rear projection type LCD projector may have a relatively large sized screen and therefore inconvenient to carry.